Support reserved names for message types

Unfortunately, our tests missed this, because all our tests with
reserved names for message types also had reserved names for the
identifiers. Added a couple tests for the new scenario, reproed,
and fixed by replacing such instances with `Any` (best we can do)

Fixes #221

CHANGELOG.md

@@ -2,6 +2,13 @@
 
 - Bump protoc support to 3.17.3
 - Use latest python versions in tests (3.6.14 3.7.11 3.8.11 3.9.6)
+- Support reserved names for message types. Previously generated invalid mypy.
+```
+message M {
+  message None {}
+  None none = 1;
+}
+```
 
 ## 2.5
 

README.md

@@ -204,6 +204,7 @@ black mypy_protobuf/main.py test/
 - [@Evgenus](https://github.com/Evgenus)
 - [@MHDante](https://github.com/MHDante)
 - [@nelfin](https://github.com/nelfin)
+- [@alkasm](https://github.com/alkasm)
 
 Licence etc.
 ------------

mypy_protobuf/main.py

@@ -174,14 +174,20 @@ def _import_message(self, name: str) -> str:
             assert name.startswith(".")
             name = name[1:]
 
+        split = name.split(".")
+
+        # Can't represent identifiers that are reserved, so mark as Any
+        # and don't bother importing
+        if any(s in PYTHON_RESERVED for s in split):
+            return self._import("typing", "Any")
+
         # Message defined in this file.
         if message_fd.name == self.fd.name:
             return name if self.readable_stubs else _mangle_global_identifier(name)
 
         # Not in file. Must import
         # Python generated code ignores proto packages, so the only relevant factor is
         # whether it is in the file or not.
-        split = name.split(".")
         import_name = self._import(
             message_fd.name[:-6].replace("-", "_") + "_pb2", split[0]
         )

proto/testproto/test.proto

@@ -75,6 +75,8 @@ message Extensions2 {
   optional bool flag = 1;
 }
 
+message None {}
+
 message PythonReservedKeywords {
   enum finally {
       continue = 1;
@@ -110,9 +112,12 @@ message PythonReservedKeywords {
   optional int64 except = 25;
   optional int64 raise = 26;
   optional int64 False = 27;
-  optional int64 None = 28;
   optional int64 True = 29;
   optional int64 class = 30;
+
+  // Test unreserved identifiers w/ reserved message names
+  optional None none = 28;
+  optional finally valid = 31;
 }
 
 // Do one with just one arg - to make sure it's syntactically correct

test/generated/testproto/test_pb2.pyi.expected

@@ -237,14 +237,22 @@ class PythonReservedKeywords(google.protobuf.message.Message):
     EXCEPT_FIELD_NUMBER: builtins.int
     RAISE_FIELD_NUMBER: builtins.int
     FALSE_FIELD_NUMBER: builtins.int
-    NONE_FIELD_NUMBER: builtins.int
     TRUE_FIELD_NUMBER: builtins.int
     CLASS_FIELD_NUMBER: builtins.int
+    NONE_FIELD_NUMBER: builtins.int
+    VALID_FIELD_NUMBER: builtins.int
+    valid: typing.Any = ...
+
+    @property
+    def none(self) -> typing.Any: ...
 
     def __init__(self,
+        *,
+        none : typing.Optional[typing.Any] = ...,
+        valid : typing.Optional[typing.Any] = ...,
         ) -> None: ...
-    def HasField(self, field_name: typing_extensions.Literal[u"False",b"False",u"None",b"None",u"True",b"True",u"and",b"and",u"as",b"as",u"assert",b"assert",u"break",b"break",u"class",b"class",u"def",b"def",u"del",b"del",u"elif",b"elif",u"else",b"else",u"except",b"except",u"for",b"for",u"from",b"from",u"global",b"global",u"if",b"if",u"import",b"import",u"in",b"in",u"is",b"is",u"nonlocal",b"nonlocal",u"not",b"not",u"or",b"or",u"pass",b"pass",u"raise",b"raise",u"try",b"try",u"while",b"while",u"with",b"with",u"yield",b"yield"]) -> builtins.bool: ...
-    def ClearField(self, field_name: typing_extensions.Literal[u"False",b"False",u"None",b"None",u"True",b"True",u"and",b"and",u"as",b"as",u"assert",b"assert",u"break",b"break",u"class",b"class",u"def",b"def",u"del",b"del",u"elif",b"elif",u"else",b"else",u"except",b"except",u"for",b"for",u"from",b"from",u"global",b"global",u"if",b"if",u"import",b"import",u"in",b"in",u"is",b"is",u"nonlocal",b"nonlocal",u"not",b"not",u"or",b"or",u"pass",b"pass",u"raise",b"raise",u"try",b"try",u"while",b"while",u"with",b"with",u"yield",b"yield"]) -> None: ...
+    def HasField(self, field_name: typing_extensions.Literal[u"False",b"False",u"True",b"True",u"and",b"and",u"as",b"as",u"assert",b"assert",u"break",b"break",u"class",b"class",u"def",b"def",u"del",b"del",u"elif",b"elif",u"else",b"else",u"except",b"except",u"for",b"for",u"from",b"from",u"global",b"global",u"if",b"if",u"import",b"import",u"in",b"in",u"is",b"is",u"none",b"none",u"nonlocal",b"nonlocal",u"not",b"not",u"or",b"or",u"pass",b"pass",u"raise",b"raise",u"try",b"try",u"valid",b"valid",u"while",b"while",u"with",b"with",u"yield",b"yield"]) -> builtins.bool: ...
+    def ClearField(self, field_name: typing_extensions.Literal[u"False",b"False",u"True",b"True",u"and",b"and",u"as",b"as",u"assert",b"assert",u"break",b"break",u"class",b"class",u"def",b"def",u"del",b"del",u"elif",b"elif",u"else",b"else",u"except",b"except",u"for",b"for",u"from",b"from",u"global",b"global",u"if",b"if",u"import",b"import",u"in",b"in",u"is",b"is",u"none",b"none",u"nonlocal",b"nonlocal",u"not",b"not",u"or",b"or",u"pass",b"pass",u"raise",b"raise",u"try",b"try",u"valid",b"valid",u"while",b"while",u"with",b"with",u"yield",b"yield"]) -> None: ...
 global___PythonReservedKeywords = PythonReservedKeywords
 
 class PythonReservedKeywordsSmall(google.protobuf.message.Message):

test/test_generated_mypy.py

@@ -17,6 +17,7 @@
 import six
 
 from google.protobuf.descriptor import FieldDescriptor
+from google.protobuf.message import Message
 
 import testproto.test_pb2 as test_pb2
 from testproto.reexport_pb2 import (
@@ -476,3 +477,11 @@ def test_casttype():
     s.email = Email("[email protected]")
     assert s.email == "[email protected]"
     s.email_by_uid[UserId(33)] = Email("[email protected]")
+
+def test_access_message_with_python_keyword_name():
+    # type: () -> None
+    with pytest.raises(AttributeError, match="module 'testproto.test_pb2' has no attribute 'asdf'"):
+        getattr(test_pb2, "asdf")
+    msg_cls = getattr(test_pb2, "None")
+    none = msg_cls()
+    assert isinstance(none, Message)